fine touch and proprioception pathways from the limbs
Last reviewed 01/2018
The posterior column spinal pathway carries sensation of:
- vibration
- proprioception
- half the touch fibres
These fibres have their cell bodies in the dorsal root ganglia.
The fibres then travel via the posterior nerve roots up the posterior column without relaying in the cord. There is an orientation within the posterior columns; those fibres originating in the lower part of the cord ascend medially.
The fibres relay in the medulla - in the nucleus gracilis (fibres from below the mid-thoracic region) and cuneatus (fibres from above this point) - and cross the midline to continue as the medial lemniscus to the thalamus.
Tertiary fibres travel via the posterior limb of the internal capsule to the sensory cortices' post-central gyrus.
Note that proprioceptive impulses also ascend to the cerebellum in the ipsilateral spinocerebellar tract (in the superficial part of the column).
blood supply to the dorsal columns